Excursion

Excursion (facultative)

Saturday 15 September FULLY BOOKED

Guided tour to Cíes Islands

(Galician Atlantic Islands Maritime-Terrestrial National Park)

The Cíes Islands

Photo: GEIB

The Cíes Islands are an archipelago off the coast of Pontevedra (Galicia, Spain). It consists of three islands, Monteagudo, do Faro and San Martiño. Since 1988 the islands are included in the Natura 2000 network and were declared National Park in 2002 as one of the best samples of the Atlantic coast and seafloor ecosystems in Spain. The National Park includes also the archipelagos of Cortegada, Sálvora, Ons and all the maritime area (86% of the National Park) around them.

Photo: GEIB

The highest peak is the Alto das Cíes (197 m) in Monteagudo which is linked to the Do Faro island by an accumulation of sand 1.200m long known as Rodas beach, in the Eastern side of the island. During high tide the sea flows between the islands in the Western side and, blocked by the beach it fills the lagoon between the sandy area and the rocks.

The land is mountainous with rough nearly vertical cliffs of more than 100 m on the Western side, and numerous caves formed by erosion from the sea and the wind. The Eastern side is less steep, covered by woods and bushes and protected from the Atlantic winds, allowing the formation of beaches and dunes.

Flora

Photo: GEIB

Sunlight and waves as well the depth and the type of substrate have a bearing on the distribution of the marine flora. Seagrasses, provide breeding places for fish and crustaceans in marine sheltered areas. Large brown algae (genera: Laminaria and Saccorhiza) form genuine sub-aquatic forests on the Western side of the islands.Terrestrial ecosystems are very different and host varied forms of plant life. Highly arid environments like beaches and dunes, force plants to make special adaptations: light colours that reflect sunlight, deep roots, water-storing bulbs, etc. Sand reeds, sea daffodils and Malcomia littorea are some of the representative species of these environments as well as the rarer Corema album and Armeria pungens. Due to the scant substrate and the exposition to strong winds full of sea salt, cliffs, only allow the survival of highly adapted plants such as Angelica pachycarpa (a plant exclusive to NW Iberia) sea fennel, seathrift or seaside chamomile. Brushwood, dominated by gorse, forms a sub-Mediterranean scrubland with species such as daphne, the narrow-leaved rockrose and the indigenous species Cytisus insularis, a broom that has only been found in the Park.

Fauna

Photo: GEIB

The marine environment covers the major part of the protected area and provides a very high degree of faunal diversity. Sea-swept rocky areas are inhabited by goose barnacles, limpets, mussels, sea acorns, etc. From the tidal line and as waters get deeper, hidden among the cracks there are sea anemones, sea urchins, winkles, crabs, gudgeons and octopi. Sandy, Maërl and gravel bottoms host very rich communities. Razor shells, cockles, clams, and others such as turbots, cuttlefish and hermit crabs can be observed.The abundance of marine organisms allows populations of marine nesting birds to thrive, such as the yellow-legged seagull and the shag, which constitute some of the world’s most important colonies and to a lesser extent the sooty tern and the storm-petrel.

Photo: GEIB

Furthermore, wintering and migrating birds such as great cormorants, gannets, Balearic shearwaters, auks and murres take advantage of these resources.In the inner areas peregrine falcons, salamanders (amphibian) reptiles such as the five-toed skink, as well as the rare butterfly Zerynthia rumina can be observed.

Alien species in the National Park

Alien plant species play a significant role in the national park. Tree stands, which cover a large area of the islands, are mainly the result of reforestation for pulp and timber production carried out in the 1950s with non native species such as eucalyptuses and pines. Their pyrophitic nature together with the dry climate of the islands and wind, make fire one of the most serious threats in this area. Of particular concern is the case of Acacia melanoxylon. It is a fast growing and highly invasive species which forms dense patches and prevents the development of native species. Widely spread on the islands it is specially threatening the dune complex of Figueiras-Muxieiro. Other alien tree species are present on the islands. Particularly striking is the plantation of Robinia pseudoacacia near the campsite.

Photo: GEIB

Sand dunes ecosystems are threatened by invasive plants such as Arctotheca calendula and Tradescantia fluminensis, which have detrimental effects on these habitats of high conservation value. Likewise cliffs are invaded by Carpobrotus. However, the number of non native invasive herbs is higher. Among them: Arundo donax, Datura stramonium, Oxalis pes-caprae, Tropaeolum majus, etc. The large brown algae Sargassum muticum which has successfully colonized the Atlantic coast represents the most important marine seaweed. The species can accumulate high biomass and may therefore be a strong competitor for space and light preventing the growth of autochthonous algae.

Photo: GEIB

The most important invasive animal species are rats (Rattus norvegicus), rabbits (Oryctolagus cuniculus) and the recently introduced American mink (Neovison vison) that could have reached the islands from the coast by swimming. The species represents a very severe threat to ground-nesting birds.

Photo: GEIB

Eradication measures to minimize the negative impacts of invasive alien species have been implemented by the national park management in collaboration with other institutions.

Tour programme

The guided tour will bring us to Monteagudo and do Faro Islands, where we will visit reference sites and find a great variety of habitats (coastal, tidal, sand dunes, cliffs, etc.). We will present alien species and discuss problems related with its prevention and eradication.

Schedule

Duration: 1-day trip. (09:00-19:00 approximately)

Departure and arrival: Pontevedra

From Pontevedra to Cangas de Morrazo by bus (30 minutes approximately)

From Cangas de Morrazo to Ciés Islands by ferry (1 hour approximately)

Free lunch (there are several restaurants) and time to enjoy the island (4 hours).

From Cíes Islands to Cangas de Morrazo by ferry (1 hour approximately)

From Cangas de Morrazo to Pontevedra by bus (30 minutes approximately)

Fee

It includes transport and guided tour.

30 €

Further Information

NEOBIOTA 2012

Conference Secretariat

neobiota2012@gmail.com

+34 609859119 // +34 626169568

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